In many ways, Jackson was sort of a revelation last year. While he had been touted as a solid prospect during his Dodger days, he never really lived up to the expectations prior to 2009. He didn't get much of an opportunity in Los Angeles (he only pitched in 19 games), and when he was traded to Tampa Bay, he struggled immensely.

In his three years with the Rays (2006-2008), he posted ERA numbers of 5.45, 5.76 and 4.42, respectively, and WHIP numbers of 1.84, 1.76 and 1.51, also respectively. Granted, Jackson wasn't as bad as his 19-26 record or ERA indicated in Tampa (his FIP numbers were 4.52, 4.90 and 4.88 with the Rays), but it was safe to say he wasn't the top prospect that everybody imagined during his Dodger days (he was rated the No. 4 prospect by Baseball America prior to the 2004 season).

However, Jackson turned it around in Detroit, and suddenly, he became one of the hottest pitchers in baseball. Jackson went 13-9 with a 3.62 ERA, and a 1.26 WHIP. When the Diamondbacks acquired him this offseason to pitch along with Dan Haren and Brandon Webb, many people deemed the Diamondbacks to have one of the most underrated rotations in baseball in 2010.

So what's Jackson have to do with Matt Cain?

In many ways, Cain and Jackson had very similar 2009 seasons. They were both guys who were better than their last couple of years prior to 2009 indicated, and they both had some skeptical numbers or qualities that made baseball fans and experts question whether or not they were as good as they were in the first half of the season in 2009. Furthermore, both Cain and Jackson had drop offs in quality down the stretch, and both their teams barely missed out on the playoffs.

With these similarities between Cain and Jackson evident (almost creepy too), who is due to have the better 2010? Who is the better pitcher in general?

If you look at their overall profiles, it's easy to see that Cain is the better pitcher. Furthermore, not only is he due for another solid season in 2010, but Jackson may be primed for a drop off in his first season in Arizona.

First, Cain has had a better history of control and command of his pitches than Jackson. Yes, Jackson posted a better walk rate than Cain last year (2.94 to 3.02), but Cain posted a better BB/K ratio than Jackson last year (2.34 to 2.30). To make matters worse for the new Diamondbacks pitcher, Jackson has struggled immensely in the past with walking hitters.

In 2008, Jackson posted a walk rate of 3.78. The season before that—his first year as a full-time starter for the Rays—he had a walk rate of 4.92.

As for Cain? He posted a walk rate of 3.56 in 2007, and 3.76 in 2008. Furthermore, he posted BB/K ratios of 2.06 and 2.04 in 2007 and 2008, respectively. Until last year, Jackson never posted a BB/K ratio over two in his Major League career. Baseball statistician Bill James, and the "CHONE" projection system, take this into great consideration as they project Jackson to have a BB/K ratio of 1.63 (James) and 2.07 (CHONE) in 2010. James projects Cain to have a BB/K ratio of 2.43, and CHONE expects it to be 2.28.

Yet control is not the only area where Cain excels over Jackson. Cain is also a better strikeout artist than Jackson.

Last season, Cain had a strikeout rate of 7.07 percent while Jackson's was 6.77. The funny thing about those strikeout numbers was that it happened to be a down year for Cain (he posted a 7.69 percent strikeout rate in 2008), and an up year for Jackson (he posted a 5.30 percent strikeout rate with the Rays in 2008). Additionally, Jackson has only posted a strikeout rate above seven once (in 2007 with the Rays), while Cain has only had a strikeout rate below seven once (2005, his rookie year).

Now, I know there were some red flags with Cain's 2009 season. His FIP didn't really correspond with his ERA (his ERA was 2.89 while his FIP was 3.89), he had a low BABIP (.268), and he also had a high left-on-base percentage (81.6 percent). While Jackson did post a similar disparaging difference between ERA and FIP (3.62 ERA to 4.28 FIP), his numbers in BABIP (.281) and left-on-base percentage (76.7 percent) were closer to the league average than Cain.

Do those numbers mean Cain will be a front line ace next year? Most likely not, since they will probably go up in terms of BABIP, and down in LOB percentage, in 2010. However, he should remain better than Jackson despite the changes in those respective categories.

For starters, Cain has a better variety of pitches than Jackson. In 2009, Cain threw his fastball 62.8 percent of the time, his slider 12.8 percent of the time, his curve 12.6 percent of the time, and his changeup 11.8 percent of the time. That's a pretty solid, four-pitch repertoire for a starting pitcher.

As for Jackson, he only threw two pitches last year—a fastball and slider. He threw his fastball 65.2 percent of the time and his slider 27.4 percent of the time. Jackson has two other pitches (a curve and change), but he only threw the pitches a combined 7.4 percent last year, showing that he doesn't have the confidence behind those third and fourth pitches like Cain.

Now, if Jackson only throws two pitches, he must be really effective with them, huh? Not exactly. Despite having a faster fastball than Cain (Jackson averaged 94.5 MPH on his fastball last year while Cain averaged 92.6 MPH), Cain was actually more effective with his fastball by leaps and bounds.

In 2009, Cain's fastball was valued at 28.6 runs above average . Jackson's? It was valued at -9.1 runs below average . Granted, Jackson's slider was very effective (it was valued at 17.7 runs above average), but considering he only has two pitches that he has confidence in, the negative value on his fastball (and it has never had positive value in his time in the Major Leagues) is a major warning sign for those who expect Jackson to duplicate his 2009 numbers in 2010.

Jackson did have an advantage over Cain in some areas such as a lower contact rate, and some categories between the two were identical (both had 0.92 GB/FB rates), but for the most part, Cain looks better than Jackson on paper, and it's no surprise to see why many projections are more skeptical of Jackson in 2010 than Cain.

Will one guy steal the National League Cy Young next year from Tim Lincecum ? Probably not. Yet in terms of effectiveness, if you have to choose between these two pitchers—you're not getting both—in a fantasy draft (or pay money for them in a live auction draft), then Cain should be the guy to go with. He may or may not be an All-Star again in 2010 (unlike Jackson, who in my mind is for sure not), but he'll still be a solid, if not stellar complement to Lincecum in the Giants rotation .